11 research outputs found
8,9-Dimethoxybenzo[b]naphtho[2,3-d]thiophene
In the title compound, C18H14O2S, the system of four fused rings is almost planar (r.m.s. deviation = 0.022â
Ă
). The C atoms of the methoxy groups deviate from the mean plane of the ring system by 0.373â
(2) and â0.104â
(2)â
Ă
. In the crystal, very weak aromatic ÏâÏ stacking interactions [shortest centroidâcentroid separation = 3.9286â
(10)â
Ă
] may help to establish the packing
Microwave-assisted Esterification of Tall Oil Fatty Acids with Methanol Using Lignin-based Solid Catalyst
During alkaline pulping significant amounts of lignin, carbohydrates (mostly hemicelluloses), and extractives (tall oil soap and turpentine) are removed from wood feedstock. In this study, the catalytic esterification of fatty acids in tall oil with methanol to produce fatty acid methyl esters under microwave irradiation was performed at 100 °C for 10â60 min. A novel heterogeneous acid catalyst tested for this purpose was synthesized from the hardwood alkali lignin that was precipitated by acidification from the black liquor from soda-AQ pulping. The comparative reaction data were obtained by using other solid catalysts, Amberlyst 15, and p-toluenesulfonic acid. The results showed the highest esterification yields of 93, 88, and 80% with the p-toluenesulfonic acid, lignin-based, and Amberlyst 15 catalysts, respectively, at 100 °C with a reaction time of 60 min, and the corresponding yield without catalyst was 20%. It was also observed that the lignin-based catalyst could be easily recovered and reused without any notable deactivation.peerReviewe
Chloridobis(ethane-1,2-diamine-Îș2N,NâČ)(3-methylpyridine-ÎșN)cobalt(III) dichloride monohydrate
In the title hydrated salt, [CoCl(C6H7N)(C2H8N2)2]Cl2·H2O, the CoIII ion exhibits a distorted octahedral coordination envirnoment defined by four N atoms of two ethane-1,2-diamine ligands, another N atom of the pyridine ligand and a Clâ ligand. The pyridine N atom and the Clâ ligand are in cis positions relative to each other. The crystal packing is dominated by intermolecular NâH...Cl, OâH...Cl and OâH...H hydrogen-bonding interactions involving the amino groups of the complex cation, the lattice water molecule and the non-coordinating Clâ anions. Weak CâH...Cl interactions consolidate the three-dimensional hydrogen-bonded network structure